Automatic circuit board plug-in system

Abstract

A circuit board plug-in system includes a frame, a mother board mounted on the frame and including a mother board connector, and a circuit board including a circuit board connector capable of mating with the mother board connector. Guide rails are mounted on the frame, and each is formed with a channel for the insertion of the circuit board. An actuator moves, under the control of a plug-in controller, the circuit board inserted into the guide rails to thereby selectively connect or disconnect the circuit board connector to or from the mother board connector. The actuator is arranged partly on the circuit board and partly on the guide rails. The plug-in controller is mounted on the frame.

What is claimed is:  
     
       1. A circuit board plug-in system comprising: 
       a frame;  
       a mother board mounted on said frame and comprising a mother board connector;  
       a circuit board comprising a circuit board connector mating with said mother board connector;  
       a pair of guide rails mounted on said frame and each being formed with a channel for insertion of said circuit board;  
       an actuator for moving said circuit board inserted into said pair of guide rails to thereby selectively connect or disconnect said circuit board connector to or from said mother board connector; and  
       a plug-in control section for controlling said actuator;  
       where in said actuator is arranged partly on said circuit board and partly on said pair of guide rails; and  
       said plug-in control section is mounted on said frame.  
     
     
       2. The system in accordance with  claim 1 , wherein said actuator comprises: 
       a locking member affixed to an end at least one of said guide rails remote from said mother board and formed with a notch; and  
       a plug-in mechanism mounted on said circuit board and comprising a rotatable disk formed with a lug for pressing an edge of the notch of said locking member when said disk is rotated, and a disk drive source for causing said disk to rotate in accordance with a drive current;  
       said plug-in control section generates a drive current for causing said disk to rotate in a preselected direction and feeds said drive current to said disk drive source; and  
       when said disk rotates with said lug pressing the edge of the notch of said locking member, said circuit board moves on said guide rails in accordance with rotation of said disk.  
     
     
       3. The system in accordance with  claim 2 , wherein said locking member and said plug-in mechanism are affixed to said circuit board and the end of said guide rail, respectively. 
     
     
       4. The system in accordance with  claim 2 , wherein said plug-in mechanism further comprises a sensor for outputting a sense signal representative of a position of said circuit board relative to said mother board; and 
       said plug-in control section generates the drive current in accordance with the sense signal output from said sensor.  
     
     
       5. The system in accordance with  claim 2 , wherein said plug-in mechanism further comprises a pair of stops for limiting a movable range of said lug of said disk; and 
       said disk drive source stops rotating said disk when said lug abuts against either one of said pair of stops.  
     
     
       6. The system in accordance with  claim 2 , wherein said plug-in mechanism causes said lug of said disk to enter the notch of said locking member for thereby preventing said circuit board from being pulled out. 
     
     
       7. The system in accordance with  claim 1 , wherein said actuator comprises: 
       an affixing block affixed to an end of at least one of said guide rails remote from said mother board and formed with a screw-threaded hole; and  
       a plug-in mechanism mounted on said circuit board and comprising a screw capable of mating with the screw-threaded hole, and a screw drive source for causing said screw to rotate in accordance with a drive current;  
       said plug-in control section generates a drive current for causing the screw to rotate in a preselected direction and feeds the drive current to said screw drive source; and  
       when the screw mates with the screw-threaded hole and rotates, said circuit board moves on said guide rails in accordance with rotation of said screw.  
     
     
       8. The system in accordance with  claim 7 , wherein said affixing block and said plug-in mechanism are mounted on said circuit board and said guide rail, respectively. 
     
     
       9. The system in accordance with  claim 7 , wherein said plug-in mechanism further comprises a sensor for outputting a sense signal representative of a position of said circuit board relative to said mother board; and 
       said plug-in control section generates the drive current in accordance with the sense signal output from said sensor.  
     
     
       10. The system in accordance with  claim 2 , wherein said circuit board connector comprises a power supply contact, a pair of signal contacts, a pair of power supply sense contacts connected to each other, a pair of signal sense contacts connected to each other, and a ground contact; 
       said mother board connector comprises a power supply pin, a pair of signal pins, a pair of power supply sense pins, a pair of signal sense pins and a ground pin respectively connectable to said power supply contact, said pair of signal contacts, said pair of power supply sense contacts, said pair of signal sense contacts and said ground contact, said pair of signal pins and said pair of signal sense pins being smaller in length than said power supply pin, said pair of power supply sense pins, and said ground pins;  
       said plug-in control section comprises a pair of loop circuits for respectively sensing conduction between said pair of power supply sense pins and conduction between said pair of signal sense pins; and  
       said plug-in control section feeds the drive current to said disk drive source for moving said circuit board to thereby calculate a first insertion position where said pair of signal sense pins are short-circuited and a second insertion position where said pair of power supply sense pins are open, and then controls said disk drive source such that said circuit board reaches a position between said first insertion position and said second insertion position.  
     
     
       11. The system in accordance with  claim 10 , wherein said plug-in control section feeds drive pulses to said disk drive source to there by move said circuit board by a unit distance for a single pulse, counts said drive pulses with a counter to thereby determine a distance that said circuit board has moved from said first insertion position to said second insertion position, and feeds a number of drive pulses that is one-half of a number of said drive pulses counted to said disk drive source to thereby move said circuit board from said second position toward said first position. 
     
     
       12. The system in accordance with  claim 7 , wherein said circuit board connector comprises a power supply contact, a pair of signal contacts, a pair of power supply sense contacts connected to each other, a pair of signal sense contacts connected to each other, and a ground contact; 
       said mother board connector comprises a power supply pin, a pair of signal pins, a pair of power supply sense pins, a pair of signal sense pins and a ground pin respectively connectable to said power supply contact, said pair of signal contacts, said pair of power supply sense contacts, said pair of signal sense contacts and said ground contact, said pair of signal pins and said pair of signal sense pins being smaller in length than said power supply pin, said pair of power supply sense pins, and said ground pins;  
       said plug-in control section comprises a pair of loop circuits for respectively sensing conduction between said pair of power supply sense pins and conduction between said pair of signal sense pins; and  
       said plug-in control section feeds the drive current to said screw drive source for moving said circuit board to thereby calculate a first insertion position where said pair of signal sense pins are short-circuited and a second insertion position where said pair of power supply sense pins are open, and then controls said screw drive source such that said circuit board reaches a position between said first insertion position and said second insertion position.  
     
     
       13. The system in accordance with  claim 12 , wherein said plug-in control section feeds drive pulses to said screw drive source to there by move said circuit board by a unit distance for a single pulse, counts said drive pulses with a counter to thereby determine a distance that said circuit board has moved from said first insertion position to said second insertion position, and feeds a number of drive pulses that is one-half of a number of said drive pulses counted to said screw drive source to thereby move said circuit board from said second position toward said first position. 
     
     
       14. The system in accordance with  claim 1 , wherein said plug-in control section controls connection and disconnection of a plurality of circuit boards from said mother board.